The present invention relates to packaging and dispensing of liquid, and more particularly concerns packaging of draft beer for optimum retention of carbon dioxide and improved dispensing.
Draft beer sold in retail outlets is dispensed from commercial metal containers that are connected to a source of pressurized gas. The commercial container has a complex spigot having internal baffling designed to control foam produced when beer is dispensed. Such spigots are expensive. In smaller containers, relatively small diameter baffle tube or "pigtail" extends from the spigot toward the bottom of the container to control foam. The barrel is pressurized by a suitable gas, such as carbon dioxide, nitrogen or air, and dispensing of contents of the container is provided under the force of the internal pressure of the container. Draft beer marketed for home use must be provided with similar pressurizing equipment or the beer must be consumed quickly form an opened container. In some arrangements, for home dispensing, a hand pump is provided or sometimes even sold with the beer container, so that the container may be repeatedly pressurized with air from the pump to enable dispensing of the contents. In general in such prior systems, the beer is dispensed only by the force of the internal pressurization.
Such internal pressurization is the source of a number of disadvantages with regard to economy of manufacture, convenience and safety. With an internal small diameter tube attached to the spigot, it is more difficult, in the capping of the filled container, to locate the tube through the opening of the container and to attach the cap. It is inconvenient and more costly to have to use some type of pressurizing pump or gas cartridge to maintain an adequate internal pressure at all times. Where a pump is employed for home use, strength of the container becomes important to avoid over pressurization of the container by a consumer and the attendant danger of explosion of a weak or defective container when over pressurized accidentally. Further, beer dispensed under such pressurization may foam excessively, particularly when a nearly empty bottle is further pressurized by a hand pump to dispense the last of the beer.
To avoid such problems and inconvenience, expense and danger, attempts have been made to package draft beer for sale to the consumer in containers that do not heed to be pressurized for dispensing of beer, but still other problems have arisen in this type of packaging.
Draft beer, when packaged for sale directly to the consumer, must have a shelf life of some 30 to 60 days, and yet retain a sufficient content of dissolved carbon dioxide so as not to be "flat" when opened by the consumer. However, where the beer is packaged in a plastic container, permeability of the container to carbon dioxide may cause an unacceptable loss of gas from the package during normal shelf life. Further, when contents of the package have been partially dispensed by the consumer and it is desired to store the package with the remaining contents for two or three days, there is a further loss of carbon dioxide and degradation of palatability. It is generally found that the remaining contents, when dispensed after the previously opened packaged has been re-sealed and stored for some time, will be flat and less palatable because of the lack of carbon dioxide content.
In the dispensing of draft beer through the spigot of a container that is not connected to an outside pressurizing source, beer flowing out tends to create a vacuum within the container, thereby stopping the flow, or at least preventing a smooth nonfoaming flow, unless adequate venting is provided. Spigots of the prior art beer containers have not provided satisfactory venting.
Initial opening and pressure release are other problems encountered with the small draft beer containers sold for consumer use. Pressure within a container of draft beer is rapidly released when the container seal is broken for initial dispensing of the beer. Such sudden pressure release may result in a projected spray of beer and gas for some distance from the container, unless the container is opened very slowly and with great care. It is difficult to avoid such undesirable spray when opening a container having presently known spigots.
Accordingly, it is an object of the present invention to provide a draft beer package and an improved spigot that will avoid or minimize above-mentioned problems.